The present invention relates to a magnetic tape recording and/or reproducing device such as tape recorder, and more particularly, to an improvement in a tape control system employed in such a device.
In some conventional magnetic tape recorders, there is provided a tape control system of the above described type including a pause switch or button. Upon pressing the pause switch or button, the forwarding of the tape is temporarily stopped without turning off the function of the tape recorder. On the assumption that the tape recorder is ready to record a certain sound, the operator first turns on the main switch, and then pushes a button or buttons such as the forwarding button which is necessary to start recording the sound. In order to check the input level of the sound, the pause button is then pushed for temporarily stopping the forwarding of the tape. While the tape is temporarily stopped, the sound is properly supplied to the tape recorder, and the tape recorder functions so as to show the input level of the sound. After checking the input level, the pause button is released for forwarding the tape.
In addition to the pause button, the tape control system of the conventional type may include an automatic tape stopper which automatically detects the end of the tape and completely turns off the tape recorder. The automatic tape stopper includes a means for detecting the end of the tape. Since recent magnetic tapes are usually constructed of an opaque magnetic tape portion where the sound is recorded and a transparent tape portion at opposite ends of the magnetic tape, the end detecting means is usually formed by a light source and a photosensitive member which are positioned so that the tape moves past the space formed between the light source and the photosensitive member. While the opaque magnetic tape portion moves past the end detecting means, a low level signal is produced therefrom to continue the forwarding operation of the tape and when, at the end of the tape, the transparent tape portion is introduced into the end detecting means, a high level signal is produced therefrom to immediately stop forwarding the tape.
However, according to this arrangement of the conventional tape control system as described above, the end detecting means not only detects the end of the tape, but also detects the beginning of the tape, since the beginning of the tape is also formed by the transparent tape. Accordingly, at the beginning of a tape, the forwarding operation of the tape may be interrupted by the end detecting means. Therefore, in the tape recorders or the like employing this type of tape control system, the operator, at the beginning of the tape, has to move the tape until the transparent tape portion has moved past the end detecting means. This operation of moving the tape gives rise to a disadvantage in operating the tape recorder, particularly when the tape is presented in a casing such as in casette tape, cartridge tape or in magazine tape.
In order to overcome these disadvantages as described above, there have been conventionally proposed various types of tape control systems one type of which is to arrange the end detecting means to become energized a predetermined period of time after turning on the forwarding button. In this arrangement, the light source is lit after the transparent tape provided at the beginning of the tape has moved past the end detecting means.
Another conventional type of tape control system includes means for intercepting the signal obtained from the end detecting means for a predetermined period of time after turning on the forwarding button. In this arrangement, the end detecting means starts functioning after the transparent tape provided at the beginning of the tape has moved past the end detecting means.
However, in either one of these conventional tape control system, there arises a drawback which interrupts the forwarding of the tape when the pause button is pushed before the transparent tape provided at the beginning completely moves past the end detecting means. More particularly, when the pause button is pushed immediately after or simultaneously with the pushing of the forwarding button, the end detecting device will start functioning after the predetermined period of time. Thus the release of the pause button after the predetermined period of time has passed would not duly forward the tape since the end detecting means operates upon detection of the transparent tape provided at the beginning of the tape.